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GCN Circulars

GCN Circulars are rapid astronomical bulletins submitted by and distributed to community members worldwide. They are used to share discoveries, observations, quantitative near-term predictions, requests for follow-up observations, or future observing plans related to high-energy, multi-messenger, and variable or transient astrophysical events. See the documentation for help with subscribing to or submitting Circulars.

Search for Circulars by submitter, subject, or body text (e.g. 'Fermi GRB').
To navigate to a specific circular, enter the associated Circular ID (e.g. 'gcn123', 'Circular 123', or '123').
Advanced Search

To narrow the search results, use advanced search syntax. This allows for specifying which circular field to search (submitter, subject, and/or body). For additional information, refer to the advanced search documentation.

Advanced Search Examples (click to copy):

subject:"Swift"
body:"GRB"
submitter:"Judith Racusin"

36149 results found.

  1. GRB 040827 - A long GRB detected by INTEGRAL
  2. GRB040825B, BVRcIc field photometry
  3. GRB040825A, BVRcIc field photometry
  4. GCN GRB OBSERBATION REPORT
  5. GRB 040825A,optical observations
  6. Increase of SGR 1806-20 activity
  7. GRB 040825A: Optical observations.
  8. GRB040825B: Correction to GCN 2657
  9. GRB 040825: Optical observations
  10. GRB 040812: Second epoch CXO Observations
  11. GRB040823,optical observation
  12. Triangulation of GRB 040816 (Konus-Wind - Helicon-Coronas-F)
  13. XRF 040812: optical observation at VLT
  14. GRB 040812: Optical counterparts of CXO sources
  15. XRF040812: possible afterglow
  16. CXO observation of GRB 040812
  17. IPN/HETE localizations of GRB040810 (=H3489)
  18. GRB 040812: Keck and LCO optical observations
  19. GRB 040812: Keck and LCO observations
  20. GRB 040812: radio observations
  21. GRB040812, optical/IR observations
  22. Konus-Wind observation of GRB040810 (=H3489)
  23. GRB 040812: a long GRB detected by INTEGRAL
  24. GRB 040810: Optical observations of a limited region
  25. IPN/HETE triangulation of GRB040802 (=H3485)
  26. GRB 040730, infrared observations
  27. GRB 040730: Optical observations
  28. GRB 040730: a long GRB detected with INTEGRAL
  29. Ongoing activity of SGR 1806-20
  30. GRB040624: optical monitoring at TNG
  31. Cancellation of IBAS/INTEGRAL GRB alerts
  32. IBAS Alert 1836: NOT a real GRB
  33. GRB040709 J,H-band observations
  34. GRB 040624: optical observations
  35. GRB 040624: optical observations at TNG and VLT
  36. MASTER: GRB 040624 optical observation after 0,48d
  37. GRB 040624: R-band observations
  38. GRB 040624, optical observations
  39. GRB 040624 - A long GRB detected with INTEGRAL
  40. GRB 030329: Rebrightening of hyperluminal ejecta.
  41. IPN Summary of SGR1806-20 Activity in 2004
  42. GRB040511: Retraction of redshift identification
  43. MASTER:HETE Alert 3259 (SRG1806-20) optical observation
  44. GRB 040606: Optical observations
  45. MASTER: HETE Alert 3274 optical observation
  46. Activivty of SGR 1806-20
  47. IPN triangulation of an intense intermediate burst from SGR1806-20
  48. GRB 040511, very fast decay?
  49. GRB 030324: Detection and Color of Host Galaxy
  50. GRB 040511: NIR observations with REM
  51. GRB040511: Redshift identifcation
  52. GRB 040511: Optical limit
  53. IBAS GRB Alerts n.1785 to 1791
  54. GRB 040511: ROTSE-III Rapid Optical Upper Limits
  55. GRB 040511: Second Epoch Optical Observations
  56. IBAS GRB Alerts 1781-4
  57. GRB 040511: Optical observations
  58. GRB 040511: Optical Observations
  59. GRB040511: Optical Observations
  60. GRB040511: Optical Observations
  61. GRB040511 (=H3218): A Long GRB Localized by HETE WXM and SXC
  62. IBAS GRB Alert number 1774: NOT a real GRB
  63. Type Ic SN2001em (off-axis GRB jet?), optical spectrum
  64. IBAS Alerts 1771 and 1772: NOT a real GRB
  65. GRB and XRF on April 27, 2004. Detection by Konus-Wind and Helicon (Coronas-F)
  66. IPN triangulation of GRB040425 (=H3183)
  67. On Line Availability of Archival HETE Fregate Data and Lightcurves
  68. GRB040422: optical observations at CrAO
  69. GRB 040423 (=H3175): A Long GRB Localized by HETE
  70. GRB 040422: ROTSE-IIIb Prompt Optical Limits
  71. GRB040422, BVRcIc field calibration
  72. GRB 040422,optical observation
  73. GRB 040422: a long GRB detected with INTEGRAL
  74. GRB 040403, deep optical observations
  75. INTEGRAL-SPI/ACS GRB data: timing correction
  76. IBAS GRB alerts 1739, 1740, 1741
  77. HETE/IPN localization of GRB040403A (=H3143, a long burst) and GRB040403B(=H3144, a short/hard burst)
  78. GRB 040403: Optical Observations
  79. GRB 040403 Optical Observations
  80. GRB 040403: Optical observations
  81. GRB 040403: optical observations
  82. GRB 040403: Optical Observations
  83. GRB 040403: a long GRB detected with INTEGRAL
  84. GRB 040329: hard burst detected by Konus-Wind and Helicon - Coronas-F
  85. IBAS GRB Alert 1694
  86. GRB 040319 (=H3128): An X-Ray-Rich GRB Localized by the HETE-2 WXM and SXC
  87. GRB 040323, a dark GRB ?
  88. short hard GRB 040322
  89. GRB 040323: a long GRB detected with INTEGRAL
  90. IBAS GRB alerts 1679, 1680, 1681
  91. GRB040223: Deep NIR NTT data re-analysis
  92. GRB 040223: XMM-Newton results
  93. GRB040223, improved XMM position
  94. IBAS Alert 1678: not a GRB
  95. GRB 031203: spectoscopic evidence for a 1998bw-like SN
  96. GRB 031203, possible supernova
  97. GRB 040228 Optical observations
  98. IPN triangulation of GRB040228 (H3066, H3067)
  99. GRB040228 : KISO optical follow-up observation
  100. GRB 040228 (=H3066?,=H3067?): A Long GRB Localized by the HETE-2 WXM

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